package com.ruoyi.redis.util;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

/**
 * @Description: 使用redis 获取表的自增长ID 
 * @ClassName: RedisIdWorker
 * @author syc
 * @date: 2022年6月10日 下午5:49:44
 */
@Component
public class RedisIdWorker {
	
    /**
     * 	开始时间戳
     */
    private static final long BEGIN_TIMESTAMP = 1640995200L;
    /**
     *	 序列号的位数
     */
    private static final int COUNT_BITS = 32;
    
    private StringRedisTemplate stringRedisTemplate;
	
    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }
    
    public long nextId(String keyPrefix) {
    	// 1.生成时间戳
    	LocalDateTime now = LocalDateTime.now();
    	long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
    	long timestamp = nowSecond - BEGIN_TIMESTAMP;
    	// 2生成序列号
    	// 2.1 获取当前日期,精确到天
    	String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
    	// 2.2自增长
    	long count =  stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
    	// 3.拼接冰并返回
    	return timestamp << COUNT_BITS | count;
    }
    
//    public static void main(String[] args) {
//    	LocalDateTime time = LocalDateTime.of(2022,1,1,0,0,0);
//		long second = time.toEpochSecond(ZoneOffset.UTC);
//		System.out.println(second);
//	}
    

}
